The present invention relates to a novel and useful railroad switching indicator mechanism for use with an internal point detector bar, and an internal point lock rod which cooperates with a locking bar.
It is often necessary to switch a railroad track to allow a train to travel therefrom to either of two tracks which split away from the first track. To achieve this result, switch mechanisms have been deployed for many years utilizing moveable rails. The moveable rails are normally referred to as points or blades, since such rails narrow to an edge at one end thereof. Known mechanisms, in the form of switching apparatuses, include an internal point lock rod which cooperates or interacts with a locking bar to hold the points against the fixed rails. In addition, an internal point detector bar is employed in order to assure that the movement of the points has taken place completely such that the points are positioned closely to the fixed rail. If such positioning does not take place within strict tolerances (¼″ or greater), this would indicate a switching obstruction which could result in a train being derailed at the switching apparatus.
Detector systems have been devised to indicate the movement of the points from one position to the other. However, it has been found that prior detector mechanism are subject to mechanical wear and, at times, break or provide a false signal as to the switching position of the points. Electronic sensors have also been devised but have not proven to be durable enough to properly operate over long periods of time.
In this regard, many systems have been devised for operating and detecting the position of the points in a switching apparatus of a railroad track. For a example, U.S. Pat. Nos. 929,363, 2,082,142, 2,348,707, and 2,698,378 utilize a point detecting connecting rod which moves with the internal points and operates switches through sensors associated with the internal point detector bar.
U.S. Pat. Nos. 4,896,850, and 6,688,559 show point position indicators which employ rotating bodies and gears that are associated with the movement of an internal point detector bar.
U.S. Pat. Nos. 4,093,163, 6,691,958, and PCT Publications WO 9427853 and WO 9920512 depict point detector mechanism having switches which engage at the two extremes of the points movement to show that the switching of the rails have been accomplished.
U.S. Pat. Nos. 5,806,809, 6,062,514, and 6,382,567 describe switching point positions sensors in which proximity detectors are used with the internal point detector bar to indicate the integrity of a switching operation.
U.S. Pat. Nos. 6,484,974, and 6,585,194 show sensors for determining the position of switching rails in which electronic sensors or employed and which may be adjustable for positioning of the same.
A railroad switching indicator which employs sensors to indicate the switching and locking of points in a switching apparatus between two positions would be a notable advance in the field of transportation.